From 204820e4dee21f074463c99c38092e49d8aa44a0 Mon Sep 17 00:00:00 2001 From: Peter Hutterer Date: Mon, 12 Mar 2018 14:32:39 +1000 Subject: [PATCH] touchpad: make sure we compare only the last 3 events for wobble We're left-shifting the bits but weren't comparing against the l_r_l mask itself. So if we get a sequence of [1, 1, 0, 1] we didn't detect a wobble because 0b1101 != 0b101 (what we're looking for). Fix this by turning it into a right shift, that way the bits fall off the mask automatic al ly y y y y . . _._v.___ Signed-off-by: Peter Hutterer (cherry picked from commit 5883ac7d98614e735e44767f3fef0e2ca03ad1ee) --- src/evdev-mt-touchpad.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c index 4ebadc25..a3d69a19 100644 --- a/src/evdev-mt-touchpad.c +++ b/src/evdev-mt-touchpad.c @@ -178,11 +178,12 @@ tp_detect_wobbling(struct tp_dispatch *tp, return; } - t->hysteresis.x_motion_history <<= 1; + t->hysteresis.x_motion_history >>= 1; if (dx > 0) { /* right move */ static const char r_l_r = 0x5; /* {Right, Left, Right} */ - t->hysteresis.x_motion_history |= 0x1; + + t->hysteresis.x_motion_history |= (1 << 2); if (t->hysteresis.x_motion_history == r_l_r) { tp->hysteresis.enabled = true; evdev_log_debug(tp->device, "hysteresis enabled\n");